This application claims the priority of German Patent Application 199 17 177.7, filed Apr. 16, 1999, and European Patent Application EP 001 07 431.9, filed Apr. 6, 2000, the disclosure of which are expressly incorporated by reference herein.
The invention relates to a motor vehicle with a supporting structure provided at at least one end of a safety passenger compartment with a crumble zone and two laterally located wheel arches in each of which a wheel is held by wheel guide members.
A motor vehicle of this kind with a front end that forms the crush or crumple zone is already known for example from German Patent 22 57 940. The wedge-shaped deflecting elements consist of sheet metal plates welded together into a block and are each fastened to the rear limiting wall of the front wheel arches. In the event of a front end impact following deformation of the crumple zone with its rolling circumference, the wheels strike the deflecting element associated with them and are supposed to be pushed diagonally outward and rearward from the wheel arches as a result of the deflecting action. As a result, under certain conditions, the front end of the safety passenger compartment can be pushed in by the front wheels. However, the circumstance is considered disadvantageous that the wheels assume a lateral overlapping position relative to the side doors of the motor vehicle and the ability of the side doors to open after an accident can be adversely affected. In addition, the effectiveness of the deflecting elements depends to a considerable degree on the design of the axle carrying the wheels and on the type of collision. Therefore, unfavorable axle or chassis designs or impact situations such as a collision with slight width overlap or a collision at a sharp angle to the central lengthwise axis of the motor vehicle can also cause an undesired block formation in which the affected wheel remains within the crumple zone and adversely affects its deformation process.
A goal of the invention is to improve a motor vehicle with a supporting structure in such a way that the opening ability of the side doors can be ensured even with a crumple zone that is almost completely collapsed as a result of a crash, when the deflecting function must be ensured largely independently of the wheel suspension or the type of collision.
This goal is achieved according to the invention by providing a motor vehicle with a supporting structure provided at at least one end of a safety passenger compartment with a crumble zone and two laterally located wheel arches in each of which a wheel held by wheel guide members is located whereby, between the safety passenger compartment and the rolling circumference of the two wheels associated with the crumple zone in the straight-ahead position, a deflecting surface running diagonally to a central lengthwise axis of the motor vehicle is provided for the associated wheel, at which wheel the wheel that is moved against the deflecting surface by the crash-produced deformation of the crumple zone is deflected past the end of the passenger compartment,
wherein the deflecting surfaces are deflecting ramps directed diagonally downward, by which the wheels upon the collapse of the crumple zone are lowered below a floor of the motor vehicle in the direction of the passenger compartment.
Advantageous embodiments of the invention are described herein and in the claims.
The wheels that move toward the safety passenger compartment when the crumple zone collapses are pushed beneath the floor of the motor vehicle by the deflecting ramps directed diagonally downward according to the invention. As a result, the so-called block formation caused by the wheels remaining within the crumple zone is avoided; the wheels interfere considerably with the deformation process of the crumple zone and their possible deformation travel is reduced accordingly. As a result of the deflection of the wheel at the associated deflection ramp that takes place in such a crash, a greater or longer area of the crumple zone can be used for deformation which has a constantly increasing force level in an accident and therefore has a much lower load imposed on the occupants.
In addition, the wheels being lowered and guided beneath the floor of the motor vehicle ensures that the side doors, even in a crumple zone that is almost completely taken up as a result of a crash, can be opened without impediment by the wheels.
If the deflecting ramps are each formed by a dent-free boundary wall of the safety passenger compartment itself, no additional parts for the deflecting ramps are necessary. This feature is especially suited for compact or subcompact vehicles whose wheels are only a short distance from the passenger compartment.
Deflecting ramps which extend over their entire vertical distance approximately at right angles to the lengthwise central plane of the motor vehicle in the event of a crash, with a simple design, ensure guidance of the wheels that is approximately parallel to the lengthwise central plane.
In order for the wheels to be deflected especially reliably beneath the vehicle floor even in a full brake application initiated before the crash and an associated downward movement of the motor vehicle nose, it has proven to be advantageous for the deflecting ramps to extend at least to the height of the rotational axes of the wheels when the wheels are completely compressed.
It has been found to be especially advantageous for the front end of the passenger compartment to rise relative to the front end structure in a frontal collision as a result of cooperation of the front wheels with the front deflecting ramp caused by the crash, and the undesired vehicle-dependent pitching effect is avoided. As a result, the front end structure cannot be overridden by the other vehicle in the accident and related increased deformation of the front end structure can be prevented. In addition, in the event of a collision, an undesired rise of the vehicle occupants in their seats is prevented to the greatest extent.
Advantageously, the deflecting ramps are formed by suitably dent-free diagonal end wall areas of the safety passenger compartment itself since no additional parts are required. In order to produce a dent-resistant design for the end wall areas with low weight, the latter preferably consist of multi-wall or multi-layer lightweight construction panels.
In a supporting structure of a motor vehicle consisting completely of lightweight design panels, the lower end wall area can be beveled in a favorable manner and adjusted to the installation position of the wheels so that the entire lower area of the end wall is designed as a deflecting ramp without additional technical expense.